Cleaving substrates produced by the semiconductor industry is a common operation to separate circuits processed on a common substrate into individual units for subsequent packaging typically in a highly automated and precise operation. During fabrication the circuits may often be sampled and tested as part of the quality control effort or the like. Since testing is not a high volume operation it is not as highly automated as production operations, and typically utilizes less automated methods to cleave the substrates or wafers into samples for testing.
As circuit features are decreased in size it has become more difficult to accurately cleave the substrates for testing by hand, or other laboratory suitable methods. Currently, an alternative to hand cleaving is to use expensive and highly accurate machinery that is available, that tends to be more than is needed in the testing lab.
Currently, there are two typical approaches to cleaving mono-crystalline substrate materials and the like. The first approach is a low-cost, low-sophistication option, which requires a highly skill-dependent procedure (based on experience and expertise and training). It involves manually aligning by human sight a substrate, and using hand tools, such as scriber pens or rudimentary cleaving apparatus. In particular the procedure involves manually scribing a line on the back side of a substrate using a scribing knife, placing the wafer over a cleaving bar from the glass industry, and manually pushing down on the work piece using two pins.
The second approach, which is more high cost but less error prone, utilizes a mechanized approach that is capital intensive in both equipment cost and operator training and, as a result, is used by approximately the top 25 semiconductor manufacturers (worldwide). Such an approach may utilize microscopic alignment to a target feature and an induced shock wave to cause cleaving. This later type of cleaving apparatus is not only complicated to make and use, but requires a much larger footprint and takes valuable space in the lab and has an ongoing high cost of operation.
These approaches have shortcomings that may include on the low tech side: a reliance on a pre-scribed cleave line in the silicon, significant human skill and or training to operate, high variability due to the human factor. On the high precision end of the available equipment spectrum the equipment available may be very large and require high capital initial expenditure, with high operating costs, complexity, and is overly precise for many operations.
Accordingly, it would be desirable to provide a machine to cleave substrates that is highly accurate, low cost and suitable for use in a testing lab or similar environment.